Andy sorry didnt get this out earlier, had to go out of town for work (yay work :) but yes, there is no acceleration limit while edming ( for heidenhain sink eroders, i doubt you'll find as much internal info from other mfctrs )
some may say that ignoring acc is just wrong but thats not from experience in this process in edm, we dont consider/remember/use the velocity of the previous servo cycle this system works and is tested i include imagebin url for the diagram specifically the acceleration is ignored during cutting ( labeled 'in gapcontrol' on diagram) and respected during positioning ( labeled 'in positioning' on diagram ). and for S&G, this weekends repair result videobin url https://videobin.org/+8v4/brq.html hth TomP tjtr33 imagebin url for control strategy diagram: http://ibin.co/1ypbbY4RbG7A On 04/14/2015 11:02 AM, andy pugh wrote: > On 11 April 2015 at 16:13, TJoseph Powderly <tjt...@gmail.com> wrote: > >> You may find that the adaptive feedrate idea is very wrong for edm. > > I think that the adaptive feed pin was introduced for wire EDM, and if > it doesn't work properly for that then it ought to change. > >> so, imo the adaptive feed is incorrect >> imo adaptive feed reduces the velocity to below the potential velocity >> (the efficient target point of the control loop) >> and thus forces inefficiency. > > If adaptive feed could be negative to retract or positive to advance > at the programmed feed rate then I think it could still work properly. > >> I'd also suggest that there are 4 common forms of edm >> Examining them shows their different TP strategies. > > I can only really see G-code and G-code reversal being useful for wire > EDM. I think that the other applications would be rather better served > by single-purpose motion control HAL modules. > > For example an orbital sink module would have X, Y and orbit > amplitude input pins and X and Y outputs that included the orbital > amplitude (This would be very much like the module I have for > polygonal turning on the lathe, except that the "spindle" speed would > be a free-running counter incrementing at a settable rate. > > The Z position output would increment/decrement depending on gap voltage. > > Are you suggesting that there is no acceleration limitation in a > normal sink eroder? > ------------------------------------------------------------------------------ BPM Camp - Free Virtual Workshop May 6th at 10am PDT/1PM EDT Develop your own process in accordance with the BPMN 2 standard Learn Process modeling best practices with Bonita BPM through live exercises http://www.bonitasoft.com/be-part-of-it/events/bpm-camp-virtual- event?utm_ source=Sourceforge_BPM_Camp_5_6_15&utm_medium=email&utm_campaign=VA_SF _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
